May 1 marks the 75th anniversary of the day a group of American soldiers boarded transports at Hampton Roads, Va., headed for battlefields in Italy. Like millions of soldiers serving in Europe and the Pacific, they'd completed their training, filled out their wills and written letters home. Each prayed he wouldn't let his buddies down when the bullets started flying. Each felt anxiety about meeting the enemy face-to-face. But this particular group of men shared other feelings too, feelings of guilt and shame, and most of all, an intense desire to prove themselves just as loyal as any other Americans.

They were the 442ndRegimental Combat Team, made up of Japanese Americans from Hawaii and from internment camps on the mainland who would etch their names in history as, per capita, the most decorated unit in U.S. military history.

Daniel Inouye, a lieutenant in the 442nd who later became a U.S. senator, wrote in his memoir, Journey to Washington: "I can see how my need to become totally involved in the war effort sprang from that invidious sense of guilt, the invisible cross lashed to the back of every nisei at the instant when the first plane bearing that rising sun appeared in the sky over Pearl Harbor. In actual fact, of course, we had nothing to feel guilty about ... and still I knew of no American of Japanese descent who did not carry this special burden."

Gen. Mark Clark, who commanded the 442nd in Italy, said, according to 442nd historian Robert Asahina in his book Just Americans: "There is no doubt in my mind that every soldier of the 442ndRCT consciously bore on his shoulders the reputation of all Japanese Americans."

Two color guards and color bearers of the Japanese-American 442nd Combat team stand at attention while their citations are read somewhere in France during World War II on Nov. 12, 1944 . They are standing on the ground where many of their comrades fell.

(ASSOCIATED PRESS)

It's "Present arms!" for members of the 442nd Regimental Combat Team, Japanese-American fighting unit, as they salute their country's flag in a brief review held the day of their arrival at Camp Shelby, Miss.

(Library of Congress)

Members of the 442nd Regimental Combat Team head out to relieve the "Lost Battalion" on Oct. 25, 1944, in the forests of eastern France.

( Courtesy Photo/Digital File_UPLOAD)

Japanese American infantrymen of the 442nd regiment are running for cover inside a building as they are targeted by German artillery in an unknown Italian town, on April 4, 1945.

(ASSOCIATED PRESS)

Each man knew the sting of racial prejudice, the jeers and insults of white people. Those from the West Coast knew the feeling of losing homes and family businesses, and of being imprisoned in camps with names like Manzanar and Tule Lake in some of America's most desolate locations. Of the more than 110,000 Japanese Americans interned, two-thirds were American citizens and half were children.

And yet, the men of the 442nd volunteered to defend America. They fought with uncommon valor in vicious campaigns in Italy and France. They captured small but crucial towns with names like Belvedere, Bruyères and Biffontaine. In their most famous battle, they fought nonstop for four days and suffered 800 casualties to rescue 211 Texan soldiers of the "Lost Battalion" in the Vosges Mountains of eastern France.

Inouye and 20 other 442ndsoldiers received the Medal of Honor. They did extraordinary things like lead "banzai" charges against German machine gun nests, expose themselves to fire to flush out the enemy and throw themselves on grenades to save their comrades. The 14,000 men who ultimately served in the 442nd received 9,486 Purple Hearts, 52 Distinguished Service Crosses, 560 Silver Stars, and 4,000 Bronze Stars.

But even this was not enough to change the minds of many back home. While fighting in France, Sgt. Jack Wakamatsu recalled finding one of his comrades sobbing in his foxhole after receiving a letter from his parents. Their house in California had been "burned down by people of the community," according to Asahina's book. Another veteran, Shig Doi, returned home to Placer County, Calif., to learn that neighbors had fired shotguns at his parents' home and set dynamite to blow up a packing shed on their farm. In Hood River, Ore., the local branch of the American Legion deliberately erased the names of 16 Japanese Americans from a wall of honor listing servicemen from the area.

We know that history often repeats itself. When we feel threatened we look for scapegoats. When we are fearful we are quick to perceive enemies, and the easiest enemies to spot are those who look different from us.

My Chinese American family has lived in the U.S. for almost a century. And yet, what would a hundred years count for if America went to war with China? Would our friends and neighbors shun us? Would the dirty looks of strangers bring back that unpleasant, prickly heat feeling of my youth when kids, and sometimes adults, would mock me with slant eyes or drive by and shout "go back to China?" I'd feel the same burden those brave Japanese Americans felt as they fought to prove themselves just as deserving of dignity as any other American.

We cannot eradicate racism. Hate, prejudice and even war are part of the human condition and always will be. To mitigate their impact requires constant vigilance, and most important, education. We must recall and honor examples in our history that remind us that being an American is based not on race, but an ideal. And when we've made mistakes, we must apologize and correct them, just as President Gerald Ford did in 1976 when he called internment "a national mistake" that "shall never again be repeated."

Members of the famed 442nd Regimental Combat Team of the United States Army, a unit composed of mostly Japanese Americans who fought in Europe salute President Bush, Thursday, May 1, 2008, in the East Room of the White House in Washington, during a ceremony celebrating Asian Pacific American Heritage Month.

(Ron Edmonds/ASSOCIATED PRESS)

President Ronald Reagan did so by signing the Civil Liberties Act of 1988, which granted reparations to surviving Japanese Americans who had been interned. Even Franklin Roosevelt, whose Executive Order 9066 to incarcerate Japanese Americans forever tarnished his legacy, later reversed course. On the day he announced the 442ndwould be formed, he told the country: "Americanism is a matter of mind and heart. Americanism is not, and never was, a matter of race or ancestry."

We all make mistakes. The important thing is that we learn from them, never forget them and teach their lessons to our children.

Andrew Lam, M.D., is a retina surgeon and author in Longmeadow, Mass., whose historical novel Repentance is based on the history of the 442ndRegimental Combat Team. He wrote this column for The Dallas Morning News.